General Information

Manufacturer: ModernaTX, Inc.

Name: mRNA-1273

Number of Shots: 2 shots, 28 days apart
Moderately or severely immunocompromised people should get an additional primary shot (third dose) at least 28 days after their second shot.

Booster Shot: People ages 18 years and older who received a Moderna primary series should get a booster shot at least 6 months after completing their primary series. You can get any of the COVID-19 vaccines authorized in the United States for your booster shot.

Type of Vaccine: mRNA

How Given: Shot in the muscle of the upper arm

Does NOT Contain: Eggs, preservatives, latex, metals

Moderna COVID-19 Vaccine Ingredients

All COVID-19 vaccine ingredients are safe. Nearly all the ingredients in COVID-19 vaccines are ingredients found in many foods—fats, sugars, and salts. The Moderna COVID-19 vaccine also contains a harmless piece of messenger RNA (mRNA). The COVID-19 mRNA teaches cells in the body how to create an effective immune response to the virus that causes COVID-19. This response helps protect you from getting sick with COVID-19 in the future. After the body produces an immune response, it discards all the vaccine ingredients, just as it would discard any substance that cells no longer need. This process is a part of normal body functioning.

All COVID-19 vaccines are manufactured with as few ingredients as possible and with very small amounts of each ingredient. Each ingredient in the vaccine serves a specific purpose as seen in the table below.

Full list of ingredients

The Moderna COVID-19 vaccine contains the following ingredients:

Type of Ingredient



Messenger ribonucleic acid (mRNA)

  • Nucleoside-modified mRNA encoding the viral spike (S) glycoprotein of SARS-CoV-2

Provides instructions the body uses to build a harmless piece of a protein from the virus that causes COVID-19. This protein causes an immune response that helps protect the body from getting sick with COVID-19 in the future.

Lipids (fats)

  • PEG2000-DMG: 1,2-dimyristoyl-rac-glycerol, methoxypolyethylene glycol

  • 1,2-distearoyl-sn-glycero-3-phosphocholine

  • BotaniChol® (non-animal origin cholesterol)

  • SM-102: heptadecane-9-yl 8-((2-hydroxyethyl) (6-oxo-6-(undecyloxy) hexyl) amino) octanoate

Work together to help the mRNA enter cells.

Salt, sugar, acid stabilizers, and acid

  • Sodium acetate

  • Sucrose (basic table sugar)

  • Tromethamine

  • Tromethamine hydrochloride

  • Acetic acid (the main ingredient in white household vinegar)

Work together to help keep the vaccine molecules stable while the vaccine is manufactured, frozen, shipped, and stored until it is ready to be given to a vaccine recipient.

Ingredients that are NOT used in COVID-19 vaccines

The above table lists ALL ingredients in the Moderna COVID-19 vaccine. There are NO ingredients in this vaccine beyond what is listed in the table. The Moderna COVID-19 vaccine has

  • No preservatives like thimerosal or mercury or any other preservatives.

  • No antibiotics like sulfonamide or any other antibiotics.

  • No medicines or therapeutics like ivermectin or any other medications.

  • No tissues like aborted fetal cells, gelatin, or any materials from any animal.

  • No food proteins like eggs or egg products, gluten, peanuts, tree nuts, nut products, or any nut byproducts (COVID-19 vaccines are not manufactured in facilities that produce food products).

  • No metals like iron, nickel, cobalt, titanium, rare earth alloys, or any manufactured products like microelectronics, electrodes, carbon nanotubes or other nanostructures, or nanowire semiconductors.

  • No latex. The vial stoppers used to hold the vaccine also do not contain latex.

Possible Side Effects

In the arm where you got the shot:

  • Pain

  • Redness

  • Swelling

Throughout the rest of your body:

  • Tiredness

  • Headache

  • Muscle pain

  • Chills

  • Fever

  • Nausea

These side effects are normal signs that your body is building protection and should go away within a few days. Talk to a doctor about taking over-the-counter medicine, such as ibuprofen, acetaminophen, aspirin (only for people ages 18 years or older), or antihistamines for any pain or discomfort experienced after getting vaccinated.

Safety Data Summary

  • Side effects that happen within 7 days of getting vaccinated are common but are mostly mild to moderate. Some people have reactions that affect their ability to do daily activities.

  • Side effects throughout the body (such as fever, chills, tiredness, and headache) are more common after the second dose of the vaccine.

  • Rare cases of myocarditis and pericarditis in adolescents and young adults have been reported after receipt of one of the two mRNA COVID-19 vaccines, Pfizer-BioNTech or Moderna. These cases occur more often after getting the second dose than after the first dose of one of these vaccines. These reports are rare and the known and potential benefits of COVID-19 vaccination outweigh the known and potential risks, including the possible risk of myocarditis or pericarditis.

All FDA-approved or authorized COVID-19 vaccines have undergone and continue to undergo the most intensive safety monitoring in U.S. history. This monitoring includes using both established and new safety monitoring systemspdf icon to make sure that COVID-19 vaccines are safe.

Learn more about vaccine safety monitoring after a vaccine is authorized or approved for use.

How Well the Vaccine Works

  • Based on evidence from clinical trials, in people ages 18 years and older, the Moderna COVID-19 vaccine was 94.1% effective at preventing laboratory-confirmed COVID-19 infection in people who received two doses and had no evidence of being previously infected.

  • The vaccine was also effective in clinical trials at preventing COVID-19 among people of diverse age, sex, race, and ethnicity categories and among people with underlying medical conditions.

  • Evidence shows mRNA COVID-19 vaccines offer similar protection in real-world conditions as they have in clinical trial settings―reducing the risk of COVID-19, including severe illness, by 90% or more among people who are fully vaccinated.

  • CDC will continue to provide updates as we learn more.

Clinical Trial Demographic Information

Clinical trials for the Moderna vaccine included people from the following racial, ethnic, age, and sex categories:


  • 79% White

  • 10% African American

  • 5% Asian

  • <3% other races/ethnicities

  • <1% American Indian or Alaska Native

  • <1% Native Hawaiian or Other Pacific Islander


  • 79% not Hispanic or Latino

  • 20% Hispanic or Latino

  • 1% unknown


  • 53% male

  • 47% female


  • 75% 18 through 64 years

  • 25% 65 years and older

Twenty-two percent (22%) of people who participated in the clinical trials had at least one condition that put them at risk of severe illness from COVID-19. The most frequent underlying medical conditions among participants were lung disease, heart disease, obesity, diabetes, liver disease, or HIV infection. Four percent (4%) of participants had two or more high-risk conditions.
Most people who participated in the trials (82%) were considered to have an occupational risk of exposure, with 25% of them being healthcare workers.

Who Should Get Vaccinated

Who Should NOT Get Vaccinated

  • If you have had a severe allergic reaction to any ingredient in an mRNA COVID-19 vaccine (such as polyethylene glycol), you should not get an mRNA COVID-19 vaccine (Moderna or Pfizer-BioNTech).

  • If you had a severe allergic reaction after getting the first dose of an mRNA COVID-19 vaccine, you should not get a second dose of either of the mRNA COVID-19 vaccines (Moderna or Pfizer-BioNTech).

  • A severe allergic reaction can cause a rapid heartbeat, difficulty breathing, swelling of the throat, or a generalized rash or hives. A person with a severe allergic reaction needs to be treated with epinephrine (often given as an EpiPen®) and should seek immediate medical attention.

If you cannot get an mRNA COVID-19 vaccine, you may still be able to get a different type of COVID-19 vaccine. Get more information for people with allergies.

Take a look at Moderna's Covid-19 website